Rubber Band Air Plane Help

The propeller appears to be misaligned with the fuselage.

Make sure the center of gravity is far enough forward. It the COG is too far back the plane won't climb.

thanks dud if u have any bearing suggestions plz tell me!

wings too high above the fuselage. Could be longer most that I build from kits were. You may want to drop the rubber band below the fuselage. Will enable you to extend it to the tail using a longer rubber band. Will increase the duration do to being able to wind it more. Rubber band should have some tension on it even when not wound. This will increase the torque at the propeller increasing air flow. This will allow you to lower the wings as close to the fuselage as possible. Looks like a lead fishing weight up front may be too much weight.

You have forgotten the pilot with happy smile!

thanks i will keep pilot there!

Your propeller's alignment appears to be dependant on your rubber band being fully stressed. When the rubber band begins to unwind it allows the prop to drop. This is forcing the plane to fly downward.

You need to solidly mount the prop housing to the fuselage to keep it in line. You may need a bearing or sleeve of some sort.

Good luck and let us know when you do get it in the air!

thank yaar u have cleared my Dough! thanks once again.

Make sure of winding in correct direction!

May I suggest that you buy & build a rubber band-powered balsa kit that has known and proven flight capabilities. That way you can study how it is constructed as well as study it's aerodynamic properties.....then go ahead and build your dream airplane!Guillows makes some superb kits that you can build in just a few hours.

check out Tower Hobbies:

www.towerhobbies.com/

Also, check out kit selections on Ebay.com

Good luck!

Your plane is attractive and original. I recommend that you hang it from the celing as a static display.

The photos definitely help!

I get the impression that you have only the top surface of your airfoil (wing) covered. If that is the case, there will be lots of turbulence on the bottom. Both top and bottom surfaces need to be smooth and tight.

It looks like the two halves of your propeller have different angles of attack, but that may just be a result of camera angle.

thank u all people above i will use ur ideas to make my plane fly .If it fly i will contact u.If u r having any other suggestion plz tell me it will help me to increase my knowledge.

I am a mechanical engineer graduated in 1983.

It's been ages since I've found someone interested in a hobby that I've been associated with since my schooling days in a convent school in kolkata. Since it was a convent school, we had a `father' - teacher, who used to build airplanes right from chuck gliders to radio controlled planes. During every annual day he would fly them. I was so fascinated and learnt the craft from him.

Regarding rubber band air planes, there are many flaws I noticed in your photographs...it would be better if we can discuss this through mails..(as I am now a businessman having my own factory, cannot devote total time for this). But since it had and is my hobby, I would definitely go out of the way to encourage people.

In fact, I bought a lot of models from "India's Hobby center" for my friends children, so that they too would be interested. But they didnt seem 2 b interested.

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Hi r...123,

Nice,

A rubber powered free flight model such as yours is a study in balance of all of the forces. You received many good suggestions up to now, but two things will help your model fly better. Increase the wing area and aspect ratio first then add dihedral. It is apparent that this model will not fly long enough to expend the energy stored in the motor because as motor torque varies, without dihedral the model will torque roll so much that the model rolls away from nearly level. Longer wing with dihedral should help. The photographs show excellent art. Pls post again if flight perf improves.

Regards,

Luther M

r...123,

Another thing:

Unless the metal used to form the prop and support the wing is very thin wall Ti, you need to use lighter materials. Also the propeller pitch seems excessive. A Guillows kit or similar build experience should help your design/build skills tremendously.

Luther M

As a kid (that was a lot of years ago) I made many rubber band powered model planes, usually from kits. We also made models similar to the one you showed. The body was made from a 1/4" by 3/8" balsa wood stick. Wings, rudder and elevators were of 1/8" balsa sticks covered with a special tissue paper. We misted the paper lightly with water and it would stretch tight when it dried. The rubber band ran the full length of the body for longer flight time.The rotational centerline of your propeller seems to be angled down rather than parallel to the planes body which would make it dive. Also the wing covering appears to be "floppy" instead of taut. I can't tell from the photo what materials you used but balsa was always our preference because of its light weight. We didn't have plastic in those prehistoric days.

What ever happened to Comet?? I LOVED building those airplanes!!

Bill

friends as i have described you about my air plane.I have
made some modifications to my model.plz give me suggestion.
1.Is propeller has proper angle of attack & blade angle,angle of twist.
2.propeller has sufficient dia?
3.Is the air foil shape is proper.
4.angle of attack for wing is 6-7 degree is it sufficient.

when i am trying to fly my plane it travels up to some
distance (1.5-2 m) but after that its nose goes upward sharply &
within second plane comes down & strikes the ground.
so friends if u have any solution then plz tell me.i have attached modified
photos here.
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